LooperThreadActivity.java

package com.google.mcommerce.sample.android.chapter06.handler;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Looper;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;

import com.google.mcommerce.sample.android.R;

public class LooperThreadActivity extends Activity {
	/** Called when the activity is first created. */

	private final int MSG_HELLO = 0;
	private Handler mHandler;

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.c06_handler_test03);
		new CustomThread().start();// 新建并启动CustomThread实例

		findViewById(R.id.send_btn).setOnClickListener(new OnClickListener() {

			@Override
			public void onClick(View v) {// 点击界面时发送消息
				String str = "hello";
				Log.d("Test", "MainThread is ready to send msg:" + str);
				mHandler.obtainMessage(MSG_HELLO, str).sendToTarget();// 发送消息到CustomThread实例

			}
		});

	}

	class CustomThread extends Thread {
		@Override
		public void run() {
			// 建立消息循环的步骤
			Looper.prepare();// 1、初始化Looper
			mHandler = new Handler() {// 2、绑定handler到CustomThread实例的Looper对象
				public void handleMessage(Message msg) {// 3、定义处理消息的方法
					switch (msg.what) {
					case MSG_HELLO:
						Log.d("Test", "CustomThread receive msg:"
								+ (String) msg.obj);
					}
				}
			};
			Looper.loop();// 4、启动消息循环
		}
	}
}